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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 19:37:10 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-15 19:37:10 +0000
commitc9addba5cc770d2d231b34f6739f32c6be8690f1 (patch)
treec643da154a95a1d163137135050bb47858a1654e /src/utf8.c
parentInitial commit. (diff)
downloadman-db-c9addba5cc770d2d231b34f6739f32c6be8690f1.tar.xz
man-db-c9addba5cc770d2d231b34f6739f32c6be8690f1.zip
Adding upstream version 2.12.0.upstream/2.12.0
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/utf8.c')
-rw-r--r--src/utf8.c138
1 files changed, 138 insertions, 0 deletions
diff --git a/src/utf8.c b/src/utf8.c
new file mode 100644
index 0000000..d766ee6
--- /dev/null
+++ b/src/utf8.c
@@ -0,0 +1,138 @@
+/*
+ * utf8.c: UTF-8 validation
+ *
+ * Based on glib's gutf8.c, which is:
+ * Copyright (C) 1999 Tom Tromey
+ * Copyright (C) 2000 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see
+ * <https://www.gnu.org/licenses/>.
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif /* HAVE_CONFIG_H */
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stddef.h>
+
+#include "attribute.h"
+
+#include "manconfig.h"
+
+#include "utf8.h"
+
+#define VALIDATE_BYTE(mask, expect) \
+ do { \
+ if (UNLIKELY ((*(unsigned char *) p & (mask)) != (expect))) \
+ goto error; \
+ } while (0)
+
+/* see IETF RFC 3629 Section 4 */
+
+static const char * ATTRIBUTE_PURE fast_validate_len (const char *str,
+ size_t max_len)
+{
+ const char *p;
+ const char *end = str + max_len;
+
+ for (p = str; p < end && *p; p++) {
+ const char *last;
+
+ if (*(unsigned char *) p < 128)
+ continue;
+
+ last = p;
+ if (*(unsigned char *) p < 0xe0) {
+ /* 110xxxxx */
+ if (UNLIKELY (end - p < 2))
+ goto error;
+
+ if (UNLIKELY (*(unsigned char *) p < 0xc2))
+ goto error;
+ } else if (*(unsigned char *)p < 0xf0) {
+ /* 1110xxxx */
+ if (UNLIKELY (end - p < 3))
+ goto error;
+
+ switch (*(unsigned char *) p++ & 0x0f) {
+ case 0:
+ /* 0xa0 ... 0xbf */
+ VALIDATE_BYTE (0xe0, 0xa0);
+ break;
+ case 0x0d:
+ /* 0x80 ... 0x9f */
+ VALIDATE_BYTE (0xe0, 0x80);
+ break;
+ default:
+ /* 10xxxxxx */
+ VALIDATE_BYTE (0xc0, 0x80);
+ }
+ } else if (*(unsigned char *) p < 0xf5) {
+ /* 11110xxx excluding out-of-range */
+ if (UNLIKELY (end - p < 4))
+ goto error;
+
+ switch (*(unsigned char *) p++ & 0x07) {
+ case 0:
+ /* 0x90 ... 0xbf */
+ VALIDATE_BYTE (0xc0, 0x80);
+ if (UNLIKELY ((*(unsigned char *) p &
+ 0x30) == 0))
+ goto error;
+ break;
+ case 4:
+ /* 0x80 ... 0x8f */
+ VALIDATE_BYTE(0xf0, 0x80);
+ break;
+ default:
+ /* 10xxxxxx */
+ VALIDATE_BYTE(0xc0, 0x80);
+ }
+ p++;
+ /* 10xxxxxx */
+ VALIDATE_BYTE(0xc0, 0x80);
+ } else
+ goto error;
+
+ p++;
+ /* 10xxxxxx */
+ VALIDATE_BYTE(0xc0, 0x80);
+
+ continue;
+
+error:
+ return last;
+ }
+
+ return p;
+}
+
+/* Validates UTF-8 encoded text. str is the text to validate; max_len is
+ * the number of bytes to validate.
+ *
+ * Note that utf8_validate() returns false if any of the max_len bytes are
+ * NUL.
+ *
+ * Returns true if the text was valid UTF-8.
+ */
+bool ATTRIBUTE_PURE utf8_validate_len (const char *str, size_t max_len)
+{
+ const char *p;
+
+ p = fast_validate_len (str, max_len);
+
+ return p == str + max_len;
+}